


Darling, It's Better Down Where It's Wetter

by waitingforjudas



Series: Judas' Kinktober 2019 [25]
Category: Teen Wolf (TV)
Genre: Bottom Derek Hale/Top Stiles Stilinski, Kinktober, Kinktober 2019, Latex, M/M, Magical Stiles Stilinski, Merman Stiles, Merpeople, Monsterfucking, Pool Sex, Xenophilia, aquatic sex, stiles is a merperson
Language: English
Status: Completed
Published: 2019-10-27
Updated: 2019-10-27
Packaged: 2021-01-04 04:10:57
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 832
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21191348
Author URL: https://archiveofourown.org/users/waitingforjudas/pseuds/waitingforjudas
Summary: Derek always wants Stiles, but he’s not sure he trusts Stiles to hold him, immobilized, in ten feet of water and fuck him. But Stilesisa merman, and hedoestrust Stiles. And besides, it might be interesting.Derek just really doesn’t want to top.Written for Kinktober 2019 prompts: Monsterfucking, Aquatic Sex, and Latex.





	Darling, It's Better Down Where It's Wetter

**Author's Note:**

> The sequel to We're Never Worth Our Fears has a full outline now (7k words). So this is late, yes, but for a (hopefully) good reason! 
> 
> Also, yes, the prompt was supposed to be shower sex, but I defy you to use monsterfucking, latex, _and_ shower sex in one work that even slightly makes sense. 
> 
>   
_Written for Kinktober 2019. Prompt list can be found at https://twitter.com/NihilistShiro/status/1162794889970511872._

“I wanna switch roles today,” Stiles said suddenly. 

Derek looked up from his book. “Okay? What role?”

Stiles waggled his eyebrows. 

Derek rolled his eyes. “You’re going to help me get into that thing.”

“Oh, I’m planning to.”

Derek rolled his eyes again. “I mean the tail, not your asshole.”

“Why can’t it be both?” Stiles grinned lasciviously. “C’mon, Der. It’s an _experience_.”

“Uh-huh.”

Stiles leaned over and put his hand on top of Derek’s book. “I won’t push if you don’t want to do it.”

“No, I do. But once I’m in that tail, I’m not moving until it’s off.”

Stiles nodded. “Uh, yeah, dude. That’s the point. Oh, my God—I know we talked about shower sex, but I don’t think we’ve really thought this through.”

Derek frowned. “What?”

“_Pool sex_, Der. We have a half-Olympic sized pool.”

“You want to… put me in ten feet of water… immobilized… and use my cock as a dildo? Am I understanding you correctly?”

“Actually,” Stiles said. “I have a bit of a different plan.”

“I don’t think I’m going to like this plan.”

“Oh, Derek,” Stiles grinned, “you’re gonna _love_ this plan.”

###

Derek loved this plan. 

Although Derek hadn’t loved the part that involved Stiles wrestling him into a latex tail, he had appreciated the part where Stiles had adjusted the positioning of the hole in the latex so it would leave his asshole uncovered instead of his cock. 

And he was definitely appreciating having Stiles holding him up. He felt weightless, and he could barely wait for Stiles to shove his cock into his hole, _hard_. 

“Stiles—Stiles, don’t tease,” he gasped. 

Stiles just chuckled, and then his arm muscles bulged slightly and Derek could feel the difference in their power as he shifted. “You love teasing, Der.” 

Derek internally cursed how long their relationship was—while it usually made for incredible, emotional, _otherworldly_ sex, it was not at the moment. 

_Namely, because _somebody_ still wasn’t fucking him_. 

Or—wait. Maybe Stiles was waiting for his cock to lube up. 

The lube that Stiles produced while he was half-shifted was… _thick_. It didn’t just dissolve on contact with water—it _stayed_. 

“How’re you feeling, Derek?” 

Derek huffed irritably. “Emp—_ty!_” Derek moaned, long and low, as Stiles’ cock fucked into his hole _hard_, covered in his own lube. 

He shuddered as he felt Stiles’ tail brush against his ankles. “Better?”

Derek nodded and nodded. “You could say that.” 

He could almost hear Stiles’ grin. “You want me to knot you, Sourwolf?”

“In the latex tail? Is that—would it work?”

“As long as you’re willing to swim for a while.”

“You think I can swim with your cock in my ass?”

“I can swim with my cock in your ass.”

Derek snorted, grinding his ass against Stiles’ thrust. “Then you swim.”

“Okay.” And like it was what Stiles had been waiting for, he started pounding into Derek’s ass until all Derek could do was groanaround his cock, fucking into him, fucking water into him, filling him and coating his insides with slick as Stiles pounded into Derek’s prostate. 

“Gonna— Gonna—” Derek cut off with a moan. 

“It’s okay, Sourwolf. I’m gonna come, too. Let go. I’ve got you.” 

Derek whined, fangs dropping and claws lengthening into Stiles’ forearms as he came, shooting into the wet latex, hoping that it wouldn’t wash right back out into the water and give them an _interesting_ pool cleaning project. 

A moment later, he felt Stiles’ cock swelling and then Stiles hissed, snarling as he slurred, “_Shit_,” and tied Derek. 

Derek shivered, leaning back onto Stiles completely, who just took his weight easily, hips twitching and tail thrashing as he worked himself deeper still and came for what felt like eternity. 

Stiles had described coming when he was half-shifted like this once. “Endless.” 

For once in his life, he’d been succinct. Derek had wished he wasn’t, but he got the feeling that it was like when he knotted Stiles (much rarer). 

It felt better on Derek’s end, anyway. 

Stiles stopped coming and just floated, raising Derek’s body above the water—which was colder for Derek, but he didn’t complain. He liked not even having to worry about floating—just having to worry about… well… nothing, really. 

Nothing at all. 

Eventually, Stiles swam them over to the poolside, and when his knot finally went down, he shifted back and helped Derek out of the water. 

“Let’s get that tail off you. What did you think, though? Seriously.”

Derek shrugged, letting Stiles work at the latex. “I liked it.”

Stiles laughed. “Evidently. Look.”

Derek glanced down and snorted. He’d _covered_ the latex in come. “At least we don’t have to clean it out of the pool.”

Stiles leaned down and kissed him. “You’re just endlessly practical, aren’t you?”

“You love it.”

“Maybe. Seriously, though, we should do this again. It was really hot.”

Derek smiled to himself. “On one condition.”

“What?”

“I’m never responsible for the tail.”

“Done.”

**Author's Note:**

> If you enjoyed, please consider leaving kudos or a comment. 
> 
> _This work was inspired by @NihilistShiro's Kinktober prompt list, available here: https://twitter.com/NihilistShiro/status/1162794889970511872 _


End file.
